code: def testConstraint(self):
      constraint_01 = lambda x: clip_ops.clip_by_value(x, -0.1, 0.0)
      constraint_0 = lambda x: clip_ops.clip_by_value(x, 0.0, 1.0)
      with self.cached_session():
          var0 = variables.Variable(
              [1.0, 2.0], constraint=constraint_01
          )
          var1 = variables.Variable([3.0, 4.0], constraint=constraint_0)
          cost = 5 * var0 + 3 * var1
          global_step = variables.Variable(
              array_ops.zeros([], dtypes.int64), name="global_step"
          )
          sgd_op = gradient_descent.GradientDescentOptimizer(3.0)
          opt_op = sgd_op.minimize(cost, global_step, [var0, var1])
  
          self.evaluate(variables.global_variables_initializer())
          # Fetch params to validate initial values
          self.assertAllClose([1.0, 2.0], self.evaluate(var0))
          self.assertAllClose([3.0, 4.0], self.evaluate(var1))
          # Run 1 step of sgd through optimizer
          opt_op.run()
          # Validate updated params
          self.assertAllClose([-0.1, -0.1], self.evaluate(var0))
          self.assertAllClose([0.0, 0.0], self.evaluate(var1))
  
imports: from tensorflow.python.distribute import cross_device_ops
  from tensorflow.python.distribute import distribute_utils
  from tensorflow.python.distribute import mirrored_strategy
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import clip_ops
  from tensorflow.python.ops import gradients_util
  from tensorflow.python.ops import resource_variable_ops
  from tensorflow.python.ops import state_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.platform import test
  from tensorflow.python.training import adam
  from tensorflow.python.training import gradient_descent
label_desc: Use image node_id 11 for calling the OptimizerTest obj's underlying member method code with example usage: obj.testConstraint() without return types